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Reversible Speed Regulation of Self-Propelled Janus Micromotors via Thermoresponsive Bottle-Brush Polymers.

ABSTRACT: This work reports a reversible braking system for micromotors that can be controlled by small temperature changes (?5?°C). To achieve this, gated-mesoporous organosilica microparticles are internally loaded with metal catalysts (to form the motor) and the exterior (partially) grafted with thermosensitive bottle-brush polyphosphazenes to form Janus particles. When placed in an aqueous solution of H₂ O₂ (the fuel), rapid forward propulsion of the motors ensues due to decomposition of the fuel. Conformational changes of the polymers at defined temperatures regulate the bubble formation rate and thus act as brakes with considerable deceleration/acceleration observed. As the components can be easily varied, this represents a versatile, modular platform for the exogenous velocity control of micromotors.

SUBMITTER: Fiedler C

PROVIDER: S-EPMC7898474 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Reversible Speed Regulation of Self-Propelled Janus Micromotors via Thermoresponsive Bottle-Brush Polymers.

Fiedler Christine C Ulbricht Christoph C Truglas Tia T Wielend Dominik D Bednorz Mateusz M Groiss Heiko H Brüggemann Oliver O Teasdale Ian I Salinas Yolanda Y

Chemistry (Weinheim an der Bergstrasse, Germany) 20210112 10

This work reports a reversible braking system for micromotors that can be controlled by small temperature changes (≈5 °C). To achieve this, gated-mesoporous organosilica microparticles are internally loaded with metal catalysts (to form the motor) and the exterior (partially) grafted with thermosensitive bottle-brush polyphosphazenes to form Janus particles. When placed in an aqueous solution of H<sub>2</sub> O<sub>2</sub> (the fuel), rapid forward propulsion of the motors ensues due to decompos ...[more]

PMID: 33205559

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